It has a TMS1700, with 1/2 the ROM and RAM of the TMS1000, but still in a 28-pin package.
I wonder what needed to be revised in the Battleship ASIC? I'm always bugged by the fact that if you press the same letter or number a 2nd time, it doesn't make a sound. So if I fire at A1 and then at A2, the 2nd A doesn't beep. It seems like that would have to be intentional, but I don't see how it is useful. It just makes me think the button isn't working.